Why We Sleep: The New Science of Sleep and Dreams

by Matthew Walker

First, when you were dreaming last night, you started to see things that were not there—you were hallucinating. Second, you believed things that could not possibly be true—you were delusional. Third, you became confused about time, place, and person—you were disoriented. Fourth, you had extreme swings in your emotions—something psychiatrists call being affectively labile. Fifth (and how delightful!), you woke up this morning and forgot most, if not all, of this bizarre dream experience—you were suffering from amnesia.